Wrist-pin puller



v Oct. 7, 1930.. H. H. FRANKS 1,777,432

WRIST PIN FULLER Filed Nov. 18, 1929 guy. 1.

- -INVENTOR H .fiv/MJ A TTORNEY Patented Oct. 7, 1930 UNITED STATESPATENT OFFICE HARRY I-I. FRANKS, OF TULSA, OKLAJZ-IDMA, .ASSIGNOR OFTHREE-FOURTHS T'O TIDAL OIL COMPANY, OF TULSA, OKLAHOMJQ, A ,COBPOEATIONOF OKLAHOMA WRIST-PIN FULLER Application filed November 1a; 1929. SerialNo. 407,977.

My invention relates towrist'pin pullers, and more particularly to adevice of that character for removing the wrist pin from the band Wheelcrank of a well drilling and pumping rig.

n rigs of this character, including a walking beam operable from a crankshaft, the beam is connected with acrank arm on the shaft by apitman andwrist pin, the

wrist pin being adapted for adjustment on the crank arm to adjust thestroke of the beam; the adjustment being effected by selective locationof the pin in a series of spaced openings in the crank arm, and as thepin must have a close, tight lit in the arm to avoid lost motion and theresultant tendency to shearing or displacement of the pin, it isfrequently difficult to remove the pin for replacement. or readjustment.

0 o It is the object of my invention to provide a device for removingthe pin without damage to the pin or its carrying arm.

In accomplishing this object, I have provided improved details ofstructure the preferred form of which is illustrated in the accompanyingdrawings, wherein: V

Fig. 1. is a perspective view of a wrist pin puller embodying myinvention, applied to a band wheel crank arm of the type commonlyemployed in well drilling and pumping rigs.

Fig. 2 is an enlarged central section of the puller, illustrating itsapplication to a wrist pin and crank arm.

Fig. 3 is a detail perspective view of the puller collar.

Referring more in detail to the drawings:

1 designates the jack post with its bearing 2 for the shaft 3 of theband wheel 4, and 5 the usual crank arm keyed to the shaft 3 andprovided with a plurality of radially spaced openings 6 for a wrist pin7 including a cylindrical body portion 8 for carrying a pitman bearing(not shown), a-tapered end 435 shank 9 for fitting within thetaperedopenings 6 of the crank arm 5, and the usual threaded ends 10 andv 11for carrying locking nuts (not shown). 1

12 designates a collar having a central ta- 53 pered bore 13 ofsubstantially greater diam- 18 matching the taper of the slots 15.

19 designates slips having outer faces curved on the axes of the pm 8and sleeve bore 13, tapered on their outer faces re- .vers'ely to thetaper. of the sleeve bore, and

wicker-ed on their inner faces to provide locking contactwith the wristpin under the conditions presently described.

The collar 12 is also preferably provided in its outer face with spannerwrench sockets 2O fora purpose presently mentioned.

, If, during operation of'the pumping rig, it should become necessary toreplace or re adjust the pin and the pin should stick inthe opening ofthe crank arm, the collar 12 is slippedover the pin until its inner endabuts against the face of the crank arm. The slips are then slipped overthe pin and into the tapered bore of the collar until a firm contact isestablished between the slips, the collar and the body of the wrist pin.The wedge members are then projected into the slots in the end of thecollar with the fiat edges bearing against the face of the crank arm.With the parts so arranged, the wedges are driven into the slots,thereby forcing the collar away from the crank arm, causing the collarto grip the pin through the slips and forcing the pin outwardly with thecollar, thereby pulling the tapered shank of the pin from the crank armopening.

When the pin has been removed the collar is driven off of the slips todisassemble the puller from the wrist pin so that it may be reassembledina new'location on the crank arm or replaced with another pin.

Should the pin stick to the arm with extraordinary firmness, a spannerwrench may be applied to the collar by means of the sockets 20 to imparta rotary jar to the pin for assistance in loosening it from the crankarm.

It is apparent that With my device a stuck pin may be removed withoutdamage to the pin and with greater ease than by the ordinary methods ofremoval.

5 hat I claim and desire to secure by Letters Patent is:

1. A Wrist pin puller including a collar having a tapered bore andtransverse end slots at opposite sides of the bore, slips adapt- 19 d tofit in the collar bore about a wrist pin,

and Wedges adapted for movement in said slots and against a pin-carryingbody to set the slips against the pin and effect movement of the pinWith the collar in response to movement of the Wedges. V

2. A Wrist pin puller including a collar having a tapered bore andtapered slots in the end of the collar containing the smaller end of thebore, slips for the collar, and

20 Wedges for the slots, each tapered on one edge to match the taper ofsaid slots. I

3. A Wrist pin puller including a collar having'a tapered bore andtapered slots in the end of the collar containing the smaller end of thebore slips for the collar, and

Wedges for the slots, each tapered on one edge to match the taper ofsaid slots and flat at the opposite edge to lie flush against the planesurface of a pin-carrying body.

4:. A Wrist pin puller including a collar having a tapered bore,transverse end slots at opposite sides of the bore and Wrench sockets inits outer face, slips adapted to fit in the collar bore about a Wristpin, and Wedges adapted for movement in said slots and against apin-carrying body to set the slips against the pin and effect movementof the pin with the collar in response to movement of the Wedges.

In testimony whereof I afiix my signature.

HARRY H. FRANK S.

